Switching device



L. R. WALLER.

SWITCHING DEVICE.

APPLICATION man NOV- 13, 1920 .Patentbd Apr.

0 O O ooao GM //1 vfifor: Lee. E. Waller both on the stepping relay andithe 'stepping @magnets. To overcome this, condensers are.

UNITED STATES PATENT OFFICE.

LEE 3. WALLER, or wnsrmounr, entient, cANADa'AssIGNoa TO WESTERN Em. TRIC COMPANY, INCORPORATED,,QF NEW YORK N. Y.', A C OR PORATION OF NEW YORK.- 4

To all whom it may concern: Be it known that L-Lnn R. WALLER, a cit zen of the United States, residing at VVestmount, in the'Province of Quebec and Do- 5 minion of Canada, have invented certain new and useful Improvementsin Switching Dcvices, of which the "following is afull, clear,

1 concise, and exact description.

This invention relates to electromagnetic switching devices and more particularly to switchesof the step-'by-step character such as those employedin telephone systems.

Switches of the type, in which an electromagnet is provided to advance the movable element from position to position in a step by-step movement, are generally arranged to be controlled both directively and automatically. To control the switch directively an operating circuit, including a stepping magnet, is adapted to be successively opened and closed by means ofa stepping relay. This relay is actuated by current impulses sent over an impulse circuit in accordance with,

some act performed by the person manipulating the apparatus.- The stepping relay, in the well-known manner, by its intermittent action creates impulses in the operating circuit which cause the steppingmagnet to advance the switch. To controlthe switch automatical ly the operating circuit, including the.

stepping magnet is arranged to. beopened and closed automatically as'by means of a set of interrupting contacts operated by the magnet itself. This method of controlling the movement of step-.by-step' switchesespecially useful where it isnecessary-to give the switch a hunting function and also for thepurpose of restoring the switch to its normal position after it has been taken for use. The sourceof current in these switch operating circuits is necessarily of comparatively high potential to insure a quick and 'certain 'uction'o'f the moving parts. The" repeated breaking of the operating circuits-tends to pit and wear' away the interruptingcontacts provided. which receive the charge that would otherwise are across the gap atthe interrupting cont-acts.

The object of the present invention is the SWITCHING nn vrcn.

. Specification of Letters Patent. Patented A1 25- 1922; Application filed November 13,1920. Serial No. 423,978.

of the stepping, magnets ofsaid switches by-step electromagnetic switches to which thepresent invention is applied. The invention in its broadest scope is applicable to step-bysstep switches of widely varyingcharacter, there being no limitation as to the construction, the number of movements or the manner of operating and controlling the same. In order to conveniently illustrate the invention, however, it is shown in connection with a plurality of ordinary single movement rotary ,step-by-step switches. Switches of this character are particularly useful. in automatic telephone systems for registering purposes. Accordingly'a few of the general elements of a register sender of the revertive impulse control type are shown.

A subscribers line is illustrated terminating in the brushes of an individual line switch 102, 103, which have access to a circuit leading to a first or. district selector switch, the brushes of which are illustrated at 111, 112. The line svi'ritch 102, 103 may be of any suitable character, preferably-a step-- by-step switch. V V p The district selector switch may be ofthe well-known power driven type, the circuits or which are controlled .by. a sequence switch 110., For a more detailed explanation ofthe individual line switch and tlieidistrict' selector switch illustratedherein, reference. is '1.

made to the application by Stearn. and Scu'd- .der, filed August 7, 1920,-serial"No.'4O2,O 11.

' The register sender includes four step-by- :step register'switches 120, 125, and

on. which thedi'gitsof a desired'designation maybe registered. Theseswitches are actuated by means of stepping magnets 124, 133,

151 and 157, respectively. For setting the register switches series ofimpulseszare transmitted over the calling line to operate in suc- .cession the several stepping magnets.

- of relay order to associate the impulse circuit in succession with the different stepping magnets and for controlling the sender circuits in other respects, a register controlling switch 1 10 is provided. Stepping magnet 109 is adapted to advance the brushes of the control switch 1 10 from position to position.

A detailed explanation will now be given showing the operation involved in setting the several register switches by impulses transmitted over the calling line and in restoring the switches to their normal positions after their :functions have been com.- pleted. Assume that the subscriber at substation 100 wishes to extend a telephone connection. The removal of his receiver. from the switchhook initiates the movement oi the individual switch having brushes 102, 103, to extend his line to an idle district selector in the way described in the above mentioned application by Steam and Sendder, filed August 7, 1920, Serial No. 402,011. Following the seizure oi the district switch, sequence switch 110 is advanced, as explained in the above mentioned application,

to a position where its contacts 104 and 105, bottom, are closed. The closure of these contacts completes animp'ulse circuit including the calling subscribers line and the windings of the stepping relay 106, individual to the register sender. This circuit may be traced from battery through the right-hand winding of relay 106, lower contact 10et,'brush 102, through the loop of the calling substation, returning by way of brush 103,. lower contact 105, left-liand winding of relay 106 to ground. Relay 106 completes a circuit from battery through the winding of slow-to-release relay 107 to ground at the front contact and armature of relay 106. Relay 107 attracts its armature and closes a circuit for the energization hen the calling subscriber manipulates his dial to transmit the first series of impulses, the first interruption of the line causes the 115101180 01 the armature of stepping relay 106. Relay 107, being slow to release, maintains its energization' and consequently holds the circuit 01 relay 108 closed. The retraction ot the armature of relay 1.06 causes the closure of the c ."cuit from ground through the ban; contact of said armature, right-bani! armature and. contact of relay 108, brush 1141- 01.? chntrol switch 140, terminal 141, winding 01 stepping magnet 12 1 01'' the lirst switch 120,

winding 01 slowtorelease relay 116 to battery and ground. Both the Stepping: magnet 12 1 and the sl owto-release relay 118 become energized in this circuit. hen, an. instant later the line circuit is again closed. at the end of the first impulse, relay 106 attracts its armature the above traced circuit is opened, and the stepping magnet deenergizes and advances brushes 11.9, 121 and 127 forward one position. Relay 118, however, being slow-to-release, maintains its armature attracted. Since the source of current in the operating circuit of magnet 124i is of comparatively high potential, the opening of this circuit at the back contact and armature of the stepping relay 106 tends to produce an are which rapidly deteriorates these contacts. To overcome this effect a condenser 115 is connected to ground in a circuit in parallel. to the circuit above traced over the back contact and arn'iature of the stepping relay 106. The circuit including condenser 115 may be traced from the operating source of current through the winding of relay 11.8, winding of magnet 12 1-, terminal 1411, brush 1141:, condenser 1115, resistance 116 to ground. llence, as the operating circuit is opened at the hack ("ontact and armature of relay 106, the energy in the circuit is consumed or stored in the condenser 115 and does not produce an arc ing effect at the interrupting contacts.

For each of the following impulses ot the series the stepping relay 106 is operated and the stepping magnet 1241 advances the brushes of the first switch 120 through one position. At the termination of the series the stepping relay 106 remains energized for a'length of time suilicient to cause the deenergization of the slow-to-release relay Relay 118 completes a circuit from battery through the winding and armature and contact of stepping magnet 109, contact and armature of relay 118, brush 117, terminal 145, segment 126 of switch 120, brush 127 to ground. The stepping magnet 109 attracts its armature and interrupts its own circuit. On deenergizing this magnet advances the brushes 113, 114C and 117 to their second position terminals where the above traced energizing circuit of said magnet is opened at brush 117.

When the subscriber next manipulates the dial 101 to transmit the second digit of the desired nnmebr, relay 106, on dcene': ing, completes a circuit "from ground. through its armature and bark contact, right-hand armature and contact o1 relay 108, brush 11st, terminal 14-2, winding 01 the stepping magnet 13%, winding oi relay 116 to battery and ground. Magnet 1 113 and relay 1.18 become energized in this circuit. At the termination of the fi rst impulse oi the series relay 106 attracts its armature and opens the above traced. circuit,permitting the magnet 133 to deenergi; i and aitlvancc the brushes 126, 129 and 1."; ot the second register switch 125 to their first position terminals. Relay 118, above erq ilained, remains energized. The sparking effect at the armature and back contact of relay 106 is prevented by the same condenser 115. This said condenser is connected in. a

circuit from battery through the winding second series of impulses relay 106 main- .tains its armature operated to permit de energization of the slow-to-release relayi118. Relay 118 now completes acircuit tronrbattery through the winding and armature of 109 is operated, interrupts its own circuit magnet 109, contact and. armature of: relay 118, brush 117, terminal 146, segment 136 of switch 125, brush 134 to ground. Magnet 109 attracts itsarmature, interrupts its own circuit and advances the brushes of the controll switch 140 to their next positiontermina s. I

On the first impulse of the third series transmitted. over the calling line, relay 106 retracts its armature and completes 'a'circu-it from ground through the back contact of said armature, right -:hand armature and contact of relay 108, brush 114, terminal 143, winding of magnet 151,- Winding of relay 118 to battery and ground. At the end of the first impulse relay 106'attracts its armature, opens theabove tracedcircuit to cause the d'eenergization of the stepping magnet 151. Magnet 15.1, on releasingits armature, advances the brushes 137, 138 and 152 of the third register switch 130,. The condenser 115 is now included in a circuit from battery throughthe windingofrelay 118, winding of stepping magnet 151, terminal 143, brush 114, condenser 115', resistance 116 to groundand consequently pre' vents sparking at the interrupting contacts of relay 106; At the end of the series of impulses relay 118 becomes deenergizedand completes a circuit from battery through the winding and armature and contact of magnet 109, contact and armature of relay 118, brush 11 7, terminal 147 segment 153 of switch 130, brush 152 to ground. Magnet and moves the brushes ofthe'control. switch -,onto their next-set of terminals.

Responsive to the first impulse of the last series transmitted trom'the calling subscribcWsstatioh, relay 106 becomes"decnergized and releases its armature. A circuit is thereuponclosed from ground through the arma ture and back'contact of said relay, righthand armat-me and contact of relay 108,

brush 114,'terminal 144, winding of step-- ping magnet157, winding of relay 118 to battery and ground: Magnet 157 and relay 118 becomes energized in. thiscircuit. At

the end of the first impulse relay 106 at-' tracts its armature and opens. the above -ci-rcult to permit the deenerglzatlonof step ping magnet 157, which, in turn, advances I the brushes 154, 155 and 158 of the register switch 135 forward one position. The circuit including condenser 115', which again serves to eliminate the. sparking efiect at the operating contacts of the stepping relay 106, maynow be traced from battery through the winding'of relay 118, winding of magnet157, terminal 144,.brush 114, condenser 1 15,'resistance 116 toground. After the last impulseof the series has beensent relay 118 finally, deenergizes and completes a circuit Magnet- 109 attracts mentioned application, filed August 7, 1920,

Serial No. 402,041, the register sender controls the operation of the district selector and succeeding switches in accordance with thedesignation recorded to establish a talking connection between the callingline and the desired called line. Following the completion of the control of the selective switches the district sequence switch 110 is advanced to a position for completing the talking circuit. In this position the-lower contacts 104 and 105 are opened to-bring about the release of the register sender. The opening of these contacts severs the impulse circuit and relay 106 becomes deenergized. After an interval the. slow-to-release relay 107 retracts its armature and opens the circuit of relay 108. f Relay .108

immediately establishes a circuit'from bat-' tery through the winding and armature and contact. of magnet 109, contact and arma ture of relay118, brush 117, terminal 160, contact and left-hand armature'of' relay 108 to ground. Magnet 109 interrupts its own circuit and advances the brushes of the control switch to the next position. In "this position of the control switch a circuit is established from battery through the winding of relay 118, winding and armature andcontact ofstepping magnet 124, segment 122, brush 121, terminal 161,brush 113.130 ground at the contact and left-hand arma-' ture of relay 108. Stepping magnet 124 .repeatedly interupts its owncircuit and ad-,

vances the brushes 1.19, 1211and 1127 forward in a step-by-step movement. During this action the contacts of the: stepping magnet 124 areprotected by a circuit including the condenser 11:5 to prevent 1 sparking.

circuit of the condenser .115 may be traced,

The.

from battery through the winding of relay 118, winding :of magnet 124., terminal 162,

brush 114, condenser 115, resistance 116 to ground. When the brushes of switch 120 have reached their normalposition, brush 121 disengages segment 122 and the inter-, rupting circuit ofmagnet 124 is opened. The switch therefore comes to rest and. after an interval relay 1'18 becomes deenergized, A

armature of relay 108.

circuit is now closed 1 1. in battery through the winding and armature and Contact of magnet 109, contact and armature of relay 113, brush 117, terminal 166, terminal 123, brush 121, terminal 161, brush 113, contact and left-hand armature of relay 108 to ground. lna net 105) advances the brushes oil the control switch to their next set of terminals.

A. circuit is now closed as :tollows for restoring the re 'ister switch 125 to its normal position: battery, through the winding of relay 118, winding of magnet 133, armature and contact oil said magnet, segment 131, ln'ush 120, terminal 103, brush 1123, con.- t-act and le'l'thand armature of relay 108 to ground. The stepping magnet 133 automatically interrupts its own contacts and advances the brushes of switch I. 25 to their normal position. Duringthe operation 0t switch 125 the contacts Off the stepping magnet 133 are protected by condenser 115 which is included in the following circuit:

battery, through the winding of relay 118,

winding'oit magnet 133, terminal 1641-, brush 1141-, condenser 115, resistance 116 to ground. IV hen the switch isitully restored brush 129 opens the circuit of the stepping magnet 133 and relay 118 later becomes ClGGIlQllglZQCl. Relay 118 completes a circuit from battery through the winding and armature and con tact of magnet 109, contact and armature of relay 11S, brush 117, terminal 165, terminal 132, brush 129, terminal. 163, brush 113 to ground at the contact and left-hand Magnet 109 ad vances the control switch 1 10 to the next position.

In a similar manner the remaining two registers 130 and 135 are automatically restored to their normal position by their respective stepping magnets 151 and 157. The contacts of these magnets are protected by the condenser 115, as explained. IVhcn the last register switch has been restored,

the register control. switch 140 moves to the position in which it is shown in the drawing and all apparatus is therefore restored to normal ready for subsequent use.

lVhat is claimed is:

1. In combination, a plurality 0'1 switches each having a movable clement, an operat ing magnet for each switch, a relay having" interrupting contacts for sending impulses to said. switches, said operating magnets being responsive to such impulses tor actuating said n'iovablc elements, interrupting contacts for each at said operating magnets for causing the automatic movementof sait movable elements, and a common means tor protecting the interrupting contacts of said relay and the contacts of all of said ma gncts.

2. In combination, a plurality of switches each having a movable element, an operating magnet for each switch, a relay having a set of contacts, means for sending impulses to said relay, said relay responding to said impulses to open and close its contacts, means controlled by said contacts for sending impulses to each of said switches, said operating magnets being responsive to such impulses for actuating the movable elements, interrupting contacts for each of said magnets for causing the automatic movement of said movable elements, and a common means for protecting the contacts of said relay and the contacts 01 all. of said magnets.

3. In combination, a plurality ot switches each having a movable element, an operatii'ig magnet for each switch, a relay having interrupting contacts for sending iu'i 1 uli-;cs to said switches, said operating magnets being responsive to such impulses for advancing said movable elements to given positions, interrupting contacts for each of said 'n'iagnets tor causing the automatic movement to normal of said movable elements, and a common means for protecting the contacts of said relay and the contacts of all of said magnets.

4:. In combination, a plurality of switches each having a movable element, an operat ing magnet for each switch, an impulse circuit, a relay having interrupting contacts for sending impulses over said circuit, means for associating said circuit with each of said magnets, said magnets being re sponsive to the impulses in said circuit for actuating said movable elements, interrupting contacts for each of said magnets for causing the automatic movement of said movable elements, and a common means for protecting the interrupting contacts of said rc. try and the contacts of all of said magnets.

5. In combination, a plurality of switches each having a movable clement, an operating magnet for each switch, an impulse circuit, a relay having interrupting contacts for sending impulses over said circuit, means for associating said impulse circuit in succession with said. magnets, said magnets being responsive to the impulses in said circuit tor actuating said. movable elements, interrupting contacts for each of said mag nets "For causing the automatic movement of said movable elements, and a common means for protecting the interrupting contacts of said relay and the contacts ()1 all 01 said magnets.

6. In con'ibii'iat-iou, uplurality of swit hes vu-h. having a movable clement, an operating magnet for each switch, an impulse circuit,

a relay having interrupting contacts for sending impulses over said circuit, a switch tor associating said impulse circuit in succession with said magnets, said magnets being responsive to the impulses in said circuit for actuating said movable elements, interrupting contacts for each of said magsaid movable elements, a circuit for each of the operating magnets, a set of interrupting contacts for opening and closing each of said circuits to cause the automatic movement of said movable elements, and a common means for protecting the interruptin contacts oi. said relay and the contacts OI all of said magnets.

8. In combination, a plurality ofswitches each having a movable element, an operating magnet for each switch, an impulse circuit, a relay having interrupting contacts for sending impulses over said circuit, means for associating said impulse circuit in succession with said. operating magnets, said operating magnets being responsive to the impulses in said circuit for actuating said movable elements, a circuit for each of said operating magnets, a set of interrupting contacts for each of said magnets for opening and closing said circuits to cause the automatic movement of said movable elements, and a common means for protecting the interrupting contacts of said relay and the contacts of all of said magnets.

9. In combination, a plurality of step-by step switches each havin a movable element, a stepping magnet For each switch, a relay having interrupting contacts forsending impulses to said switches, said stepping magnets being responsive to such impulses for actuating the movable elements, inter- 1 rupting contacts for each of said stepping magnets for causing the automatic movement of said movable elements, and a common means for protecting the interrupting contacts of said relay and the contacts of all of said magnets.

10. In combination, a plurality of step-by,- step switches each having a movable element, a stepping magnet for each switch, a relay having interrupting contacts for sending impulses to said switches, a step-by-step auxiliary switch for associating in succession said relay with said step-by-step switches, said stepping magnets being responsive to such impulses for actuating the movable elements, interrupting contacts for each of said stepping magnets for causing automatic movement of said movable-elements, and a common means for protecting the interruptingcontacts of said relay and the contacts of all of said magnets.

11. I11 combination, a plurality of step-bystep switches each having a movable element, a stepping magnet for each switch, a relay having interrupting contacts for sending impulses to Said switches, said stepping magnets being responsive to such impulses for actuating said movable elements, interrupting contacts for each of said stepping magnets for causing the automatic movement of the movable elements, and a single device for protecting the interrupting contacts of said relay and the contacts of each of said magnets.

12. In combination, a plurality of switches each having a movable element, an operating magnet for'each switch, a relay having interrupting contacts for sending impulses to said switches, said operating magnets be= ing responsive to such impulses for actuating said movable elements, interrupting contacts for each of said operating magnets for causing the automatic movement of said movable elements, and a single condenser for protecting the interrupting contacts of said relay and thecontacts of all of said magnets. V

13. In combination, a plurality of switches each having a movable element, an operating magnet for each switch, a relay having interrupting contacts for sending impulses to said switches, said operating magnets being responsive to such impulses for actuatin g said movable elements, interrupting contacts foreach of said operating magnets for causing the automatic movement of said movable elements, a condenser, and means for associating said condenser with the interrupting contacts of said relay and with the contacts of all of said magnets.

14. In combination, a plurality of switches each having a movable element, an operating magnet for each switch, a relay having interrupting contacts for sending impulses movable elements, a condenser, and a switch 7 for associating said condenser in succession with the mterrupting contacts of said relay and with the contacts of said operating magnets.

In witness whereof, I hereunto subscribe my name this 9th day of November, A. D. 1920.

men R. WALLER. 

